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Complex Vegetation Dynamics At The Fire-Grazing-Drought Nexus, Christine H. Bielski

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

The discipline of ecology long ago moved away from viewing systems as static entities where disturbance processes, environmental stochasticity, and spatiotemporal variability play minor roles in determining ecosystem structure and function. Ecological theory continue to develop frameworks and statistical techniques capable of describing the inherent complexity in natural systems. However, in dealing with the complexity in nature, many applied disciplines have yet to adopt such frameworks or statistical techniques. The objective of this study was bridge the gap between ecological theory and application by using complex systems theory to describe grassland vegetation dynamics at the fire-grazing-drought nexus. Chapters 2 and …

Integration Of Plant Defense Traits With Biological Control Of Arthropod Pests: Challenges And Opportunities, Julie A. Peterson, Paul J. Ode, Camila Oliveira-Hofman, James D. Harwood

Department of Entomology: Faculty Publications

Crop plants exhibit a wide diversity of defensive traits and strategies to protect themselves from damage by herbivorous pests and disease. These defensive traits may be naturally occurring or artificially selected through crop breeding, including introduction via genetic engineering. While these traits can have obvious and direct impacts on herbivorous pests, many have profound effects on higher trophic levels, including the natural enemies of herbivores. Multi-trophic effects of host plant resistance have the potential to influence, both positively and negatively, biological control. Plant defense traits can influence both the numerical and functional responses of natural enemies; these interactions can be …

Sandhill Crane Roost Selection, Human Disturbance, And Forage Resources, Aaron T. Pearse, Gary L. Krapu, David A. Brandt

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Sites used for roosting represent a key habitat requirement for many species of birds because availability and quality of roost sites can influence individual fitness. Birds select roost sites based on numerous factors, requirements, and motivations, and selection of roosts can be dynamic in time and space because of various ecological and environmental influences. For sandhill cranes (Antigone canadensis) at their main spring staging area along the Platte River in south-central Nebraska, USA, past investigations of roosting cranes focuse donphysical channel characteristics related to perceived security as motivating roost distribution.We used 6,310 roost sites selected by 313 sandhill cranes over …

Prehistoric Pathoecology As Represented By Parasites Of A Mummy From The Peruaçu Valley, Brazil, Karl Reinhard, Adauto Araújo

Karl Reinhard Publications

Paleopathologists have begun exploring the pathoecology of parasitic diseases in relation to diet and environment. We are summarizing the parasitological findings from a mummy in the site of Lapa do Boquete, a Brazilian cave in the state of Minas Gerais. These findings in context of the archaeology of the site provided insights into the pathoecology of disease transmission in cave and rockshelter environments. We are presenting a description of the site followed by the evidence of hookworm, intestinal fluke, and Trypanosoma infection with resulting Chagas disease in the mummy discovered in the cave. These findings are used to reconstruct the …

Viral Zoonoses That Fly With Bats: A Review, Alfonso Calderon, Camilo Guzman, Jorge Salazar-Bravo, Luiz Tadeu Figueiredo, Salim Mattar, German Arrieta

MANTER: Journal of Parasite Biodiversity

Emerging infectious diseases are a growing threat to human health and a great challenge for global medical attention systems. Governmental agencies in tropical regions with abundant zoonotic pathogens should implement an active vigilance/monitoring model in bat reservoir populations because of their species richness, abundance and dispersal capabilities. Chiropterans represent approximately 20% of all mammal species, the second largest order in terms of number of species after rodents. Importantly, bats constitute natural reservoirs for potential infection of humans of several infectious disease agents such as Coronavirus, Filovirus, Lyssavirus, Paramyxovirus, and Flavivirus. Local disease outbreaks caused by new pathogens can …

Population Characteristics Of Human-Commensal Rodents Present In Households From Mérida, Yucatán, México, Jesús Alonso Panti-May, Silvia F. Hernández-Betancourt, Marco A. Torres-Castro, Carlos Machaín-Williams, Nohemi Cigarroa-Toledo, Lorenzo Sodá, Gabriela López-Manzanero, Josué R. Meza-Sulú, Victor M. Vidal-Martínez

MANTER: Journal of Parasite Biodiversity

Anthropocommensal rodents live in close proximity to humans in many habitats around the world. They are a threat to public health because of the pathogens they carry. Recent studies in Mérida, Yucatán, México, have shown that commensal rodents harbor potential zoonotic pathogens such as bacteria, helminths, and viruses. In this study, we describe reproductive and demographic parameters of house mice and black rats present in households from Mérida, Yucatán, México, a municipality located in a tropical region in southern México. Rodents were trapped in 142 households within the municipality of Mérida from 2011 to 2014. A total of 832 rodents …

Current Knowledge Of Studies Of Pathogens In Colombian Mammals, Viviana Gonzalez-Astudillo, Héctor E. Ramírez-Chaves, Joerg Henning, Thomas R. Gillespie

MANTER: Journal of Parasite Biodiversity

Mammals provide an important ecological habitat or niche space to microbial diversity, protistans (or protozoans) and metazoan parasites that can have profound effects on both human and animal health. Thus, understanding the status of mammalian species as hosts for pathogens holds relevance, especially during this time of anthropogenic environmental change. Despite the great diversity in the mammal fauna of Colombia, data in the literature on the occurrence of parasites and pathogens in these mammals are scarce and widely scattered. In order to understand the state of the knowledge of pathogens carried by wild mammals in Colombia, a systematic review of …

Using Ecological Production Functions To Link Ecological Processes To Ecosystem Services, Randall Jf Bruins, Timothy J. Canfield, Clifford Duke, Larry Kapustka, Amanda M. Nahlik, Ralf B. Schäfer

United States Environmental Protection Agency: Publications

Ecological production functions (EPFs) link ecosystems, stressors, and management actions to ecosystem services (ES) production. Although EPFs are acknowledged as being essential to improve environmental management, their use in ecological risk assessment has received relatively little attention. Ecological production functions may be defined as usable expressions (i.e., models) of the processes by which ecosystems produce ES, often including external influences on those processes. We identify key attributes of EPFs and discuss both actual and idealized examples of their use to inform decision making. Whenever possible, EPFs should estimate final, rather than intermediate, ES. Although various types of EPFs have been …

Applications Of Time-Lapse Imagery For Monitoring And Illustrating Ecological Dynamics In A Water-Stressed System, Emma Brinley Buckley

School of Natural Resources: Dissertations, Theses, and Student Research

Understanding and perceiving the natural world is a key part of management, policy, conservation, and inevitably for our future. Increased demand on natural resources has heightened the importance of documenting ecosystem changes, and knowledge-sharing to foster awareness. The advancement of digital technologies has improved the efficiency of passive monitoring, connectivity among systems, and expanded the potential for innovative and communicative approaches. From technological progression, time-lapse imagery has emerged a valuable tool to capture and depict natural systems. I sought to enhance our understanding of a water-stressed system by analyzing imagery, in addition to integrating images with data visualization to illustrate …

Morphological And Molecular Identification And Characterization Of Dry Bean Fungal Root Rot Pathogens In Zambia, Chikoti Mukuma

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Dry bean is among the most important food legume crops for direct human consumption in Latin America and Africa. Recently, root and crown rot (RCR) has emerged as an important production constraint. Root and crown rot often involve fungal complexes. Thus, the straw, detached leaf, cup and stem tests were compared on their ability to detect the most common pathogens reported to be associated with RCR: Fusarium solani, Fusarium oxysporum, Pythium ultimum, Rhizoctonia solani and Macrophomina phaseolina.Significant differences (P

Next Generation Sequencing (NGS), conventional Polymerase Chain Reaction (PCR), and classical fungal culturing methods were compared in identification of …

Gaur (Bos Gaurus) Abundance, Distribution, And Habitat Use Patterns In Kuiburi National Park, Southwestern Thailand, Supatcharee Tanasarnpaiboon

School of Natural Resources: Dissertations, Theses, and Student Research

Population status of gaur (Bos gaurus), a wild cattle, in most habitats where they are present, is still unknown. As the use of camera traps in wildlife studies are widespread, I developed photographic individual identification procedures and utilized encounter histories of gaur individuals from camera trap data to estimate gaur abundance and density using the spatially explicit capture-recapture analysis. The study was conducted at Kuiburi National Park, southwestern Thailand, comprised of dry evergreen forest, moist evergreen forest, and man-modified secondary forest during November 2013- January 2015. I conducted 71 direct observations in a savannah-like habitat area to observe …

Eastern Wild Turkey Nest Site Selection In Two Frequently Burned Pine Savannas, Andrew R. Little, Nathan P. Nibbelink, Michael J. Chamberlain, L. Mike Conner, Robert J. Warren

School of Natural Resources: Faculty Publications

Introduction: Reproductive success is a critical factor affecting avian demographics and can be influenced by many factors including nesting chronology, predation risk, and fine-scale nest site selection.

Methods: We modeled the relative influences of habitat-related covariates at six spatial scales (nest site: 15-, 40-, 80-, 120-, 160-, and 200-m radii) on Eastern wild turkey (Meleagris gallopavo silvestris) nest site selection in two pine savannas managed by frequent prescribed fire (≤3 years) in southwestern Georgia during 2011–2013.

Results: Nest site (15-m scale) habitat metrics (mean visual obstruction [cm] and canopy closure [%]) had the greatest influence on nest site …

Export Of Insect Ecosystem Services From Hayed Native Prairie, Wayne J. Ohnesorg

Department of Entomology: Dissertations, Theses, and Student Research

Natural areas, such as prairie, have the potential to provide the benefits of pest suppression and pollination for agricultural production. In Nebraska, prairie is often used for hay production. The impact of prairie hay production management practices on beneficial arthropods is not well understood. Four prairie hay meadows adjacent to row crop fields were selected in northeast Nebraska. The goal was to assess the impact of haying them on beneficial arthropods and the movement of natural enemies into adjacent crop fields. Three management practices were evaluated for hay harvested from prairie meadows one cut per growing season, two cuts per …

Elderly People And Their Information Needs, Nelson Edewor, Osaze Patrick Ijiekhuamhen, Uche P. Emeka-Ukwu

Library Philosophy and Practice (e-journal)

This study is aimed at exploring the information behavior of the elderly people amongst us. A survey research design was adopted. Four objectives were set for the study and the interview was used to elicit information from respondents. Findings showed that 63% were male while 37% were female. Findings also reveal that the information needs of elders covered health conditions (98%), pension/finance (92%), government policies (34%), current affairs (53%), and transport (63%) among others. The most preferred source of information as revealed by the study is the use of family members (98%). This is followed by radio/television (92%). Use of …

3d Tool Evaluation And Workflow For An Ecological Approach To Visualizing Ancient Socio-Environmental Landscapes: A Case Study From Copan, Honduras, Heather Richards-Rissetto, Shona Sanford-Long, Jack Kerby-Miller

Department of Anthropology: Faculty Publications

Architectural reconstructions are the centerpieces of ancient landscape visualization. When present, vegetation is relegated to the background, resulting in underutilized plant data—an integral data source for archaeological interpretation—thus limiting the capacity to take advantage of 3D visualization for studying ancient socio-environmental dynamics. Our long-term objective is to develop methods of 3D landscape visualization that have value for examining changes in land use and settlement patterns. To begin to work toward this objective, we have (1) identified 3D tools and techniques for vegetation modeling and landscape visualization, (2) evaluated the pros and cons of these tools, (3) investigated biological and ecological …

Serum Chemistry, Blood Gas, And Physiological Measures Of Sandhill Cranes Sedated With Alpha-Chloralose, Richard R. Sim, Barry K. Hartup

Proceedings of the North American Crane Workshop

Capture techniques that lessen handling stress may also lessen pathologic influences on physiologic measures, improving the validity of these measures for use in individual health assessment of freeranging wildlife. Since 1990, the International Crane Foundation (ICF) has successfully used chemical immobilization with alpha-chloralose (AC; C₆H₁₁Cl₃O₆), a chloral derivative of glucose, to facilitate captures of sandhill cranes (Grus canadensis tabida) for ecological studies (Hayes et al. 2003). Although this chemical has been used orally for the immobilization of many species, the physiologic effects of AC are not well understood in cranes. …

Distribution, Densities, And Ecology Of Siberian Cranes In The Khroma River Region Of Northern Yakutia In Northeastern Russia, Inga P. Bysykatova, Gary L. Krapu, Nicolai I. Germogenov, Deborah A. Buhl

Proceedings of the North American Crane Workshop

The Siberian crane (Grus leucogeranus) is the third rarest crane species in the world with a breeding range now centered on 3 core areas and a buffer zone in the arctic of northern Yakutia in northeastern Russia. During 16 July-2 August 2009, we undertook ground surveys within the Khroma River core breeding area, surrounding buffer zone, and lands lying to the west of the known breeding range to estimate densities and determine habitat use and social status of Siberian cranes. A total of 142 Siberian cranes were sighted (including 55 pairs) at 54 locations with 32 cranes (including 13 pairs) …

Late Holocene Expansion Of Ponderosa Pine (Pinus Ponderosa) In The Central Rocky Mountains, Usa, Jodi R. Norris, Julio L. Betancourt, Stephen T. Jackson

United States National Park Service: Publications

Aim: Ponderosa pine (Pinus ponderosa) experienced one of the most extensive and rapid post-glacial plant migrations in western North America. We used plant macrofossils from woodrat (Neotoma) middens to reconstruct its spread in the Central Rocky Mountains, identify other vegetation changes coinciding with P. ponderosa expansion at the same sites, and relate P. ponderosa migrational history to both its modern phylogeography and to a parallel expansion by Utah juniper (Juniperus osteosperma).

Location: Central Rocky Mountains, Wyoming and Montana, and Black Hills, Wyoming and South Dakota, USA.

Methods: Plant macrofossils were analysed in 90 middens …

Prehistoric Human Impact On Tree Island Lifecycles In The Florida Everglades, Traci Ardren, Justin P. Lowry, Melissa Memory, Kelin Flanagan, Alexandra Busot

United States National Park Service: Publications

The current study provides a fine-grained analysis of evidence for sustained pre-Columbian human occupation and socio-ecological interaction within Everglades National Park. Utilizing archaeological data on dietary and cultural patterns recovered from recent excavations at a prehistoric tree island site, we argue the role of ancient human populations in the formation or augmentation of tree islands should be incorporated into environmental models of the tree island lifecycle. High phosphorus levels in human waste, especially the largely organic waste of prehistoric populations, as well as other anthropogenic factors have not been adequately factored into current environmental models of tree island formation or …

Hydrothermal Monitoring In Yellowstone National Park Using Airborne Thermal Infrared Remote Sensing, C. M.U. Neale, C. Jaworowski, H. Heasler, S. Sivarajan, A. Masih

United States National Park Service: Publications

This paper describes the image acquisition and processing methodology, including surface emissivity and atmospheric corrections, for generating surface temperatures of two active hydrothermal systems in Yellowstone National Park. Airborne thermal infrared (8–12 μm) images were obtained annually from 2007 to 2012 using a FLIR SC640 thermal infrared camera system. Thermal infrared image acquisitions occurred under clear-sky conditions after sunset to meet the objective of providing high-spatial resolution, georectified imagery for hydrothermal monitoring. Comparisons of corrected radiative temperature maps with measured ground and water kinetic temperatures at flight times provided an assessment of temperature accuracy. A repeatable, time-sequence of images for …

Hydrothermal Monitoring In Yellowstone National Park Using Airborne Thermal Infrared Remote Sensing, C. M. U. Neale, C. Jaworowski, H. Heasler, S. Sivarajan, A. Masih

Daugherty Water for Food Global Institute: Faculty Publications

This paper describes the image acquisition and processing methodology, including surface emissivity and atmospheric corrections, for generating surface temperatures of two active hydrothermal systems in Yellowstone National Park. Airborne thermal infrared (8–12 μm) images were obtained annually from 2007 to 2012 using a FLIR SC640 thermal infrared camera system. Thermal infrared image acquisitions occurred under clear-sky conditions after sunset to meet the objective of providing high-spatial resolution, georectified imagery for hydrothermal monitoring. Comparisons of corrected radiative temperature maps with measured ground and water kinetic temperatures at flight times provided an assessment of temperature accuracy. A repeatable, time-sequence of images for …

Endangered Species Research In Hawaii: The Early Years (1965–87), Michael J. Scott, Cameron B. Kepler

United States Geological Survey: Staff Publications

Hawaii is an ecologically isolated archipelago 2,500 miles from the nearest continent. Its isolation resulted in a taxonomically unbalanced flora and fauna with remarkable examples of adaptive radiation among those groups of organisms that won the dispersal sweepstakes. It was one of the last oceanic island groups to be populated by humans, about 900 A.D. by Polynesian travelers and in 1778 by Europeans. Relatively recent colonization by humans did not save it, however, from the biodiversity losses suffered by other isolated archipelagos—it only delayed them (Scott and others, 1988; Pratt and others, 2009a).

Patuxent’S Long-Term Research On Wolves, David L. Mech

United States Geological Survey: Staff Publications

The gray wolf (Canis lupus) was one of the first species placed on the Endangered Species List in 1967. The Endangered Species Act of 1973 legally protected the wolf along with other listed species. Patuxent Wildlife Research Center (Patuxent) in Laurel, MD, began its Endangered Wildlife Program in 1966, and U.S. Fish and Wildlife Service (USFWS) biologist Ray Erickson was assigned to lead it. In 1973, I was transferred to the program from Region 3 of the USFWS, having been employed there since 1969 to study wolves in Minnesota. Endangered Species Act protection of the wolf fostered its …

White-Tailed Deer (Odocoileus Virginianus) Subsidize Gray Wolves (Canis Lupus) During A Moose (Alces Americanus) Decline: A Case Of Apparent Competition?, Shannon M. Barber-Meyer, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Moose (Alces americanus) in northeastern Minnesota have declined by 55% since 2006. Although the cause is unresolved, some studies have suggested that Gray Wolves (Canis lupus) contributed to the decline. After the Moose decline, wolves could either decline or switch prey. To determine which occurred in our study area, we compared winter wolf counts and summer diet before and after the Moose decline. While wolf numbers in our study area nearly doubled from 23 in winter 2002 to an average of 41 during winters 2011–2013, calf:cow ratios (the number of calves per cow observed during winter …

Patuxent’S Long-Term Research On Wolves, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

The gray wolf (Canis lupus) was one of the first species placed on the Endangered Species List in 1967. The Endangered Species Act of 1973 legally protected the wolf along with other listed species.

Patuxent Wildlife Research Center (Patuxent) in Laurel, MD, began its Endangered Wildlife Program in 1966, and U.S. Fish and Wildlife Service (USFWS) biologist Ray Erickson was assigned to lead it. In 1973, I was transferred to the program from Region 3 of the USFWS, having been employed there since 1969 to study wolves in Minnesota.

Endangered Species Act protection of the wolf fostered its quick …

Bibliographia Phytosociologica Et Floristica Mongolia: Pars Iv, Werner Hilbig

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

In Ergänzung zu den bisherigen drei Teilen der Bibliographie vegetationskundlicher, vegetationsökologischer, floristischer und pflanzengeographischer Arbeiten über die Mongolei wird in dieser Arbeit Teil IV der Bibliographie vorgelegt. Er umfasst im Wesentlichen den Zeitraum 2007 bis 2014. Auch Publikationen zur Vegetationsgeschichte und zum botanischen Naturschutz werden berücksichtigt.

English summary:

In addition to the hitherto existing three parts of the bibliography of geobotanical, ecological, floristic and plant-geographical papers on Mongolia the part IV of the bibliography is given. It comprises in the main point the period from 2007 until 2014. In addition, publications on vegetation history and botanical nature protection are considered.

Stress-Induced Changes In Abundance Differ Among Obligate And Facultative Endosymbionts Of The Soybean Aphid, Laramy S. Enders, Nicholas Miller

Department of Entomology: Faculty Publications

Bacterial endosymbionts can drive evolutionary novelty by conferring adaptive benefits under adverse environmental conditions. Among aphid species there is growing evidence that symbionts influence tolerance to various forms of stress. However, the extent to which stress inflicted on the aphid host has cascading effects on symbiont community dynamics remains poorly understood. Here we simultaneously quantified the effect of host-plant induced and xenobiotic stress on soybean aphid (Aphis glycines) fitness and relative abundance of its three bacterial symbionts. Exposure to soybean defensive stress (Rag1 gene) and a neurotoxic insecticide (thiamethoxam) substantially reduced aphid composite fitness (survival 9 reproduction) …

The Influence Of A Severe Reservoir Drawdown On Springtime Zooplankton And Larval Fish Assemblages In Red Willow Reservoir, Nebraska, Jason A. Deboer, Christa M. Webber, Taylor A. Dixon, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Reservoirs can be dynamic systems, often prone to unpredictable and extreme waterlevel fluctuations, and can be environments where survival is difficult for zooplankton and larval fish. Although numerous studies have examined the effects of extreme reservoir drawdown on water quality, few have examined extreme drawdown on both abiotic and biotic characteristics. A fissure in the dam at Red Willow Reservoir in southwest Nebraska necessitated an extreme drawdown; the water level was lowered more than 6 m during a two-month period, reducing reservoir volume by 76%. During the subsequent low-water period (i.e., post-drawdown), spring sampling (April-June) showed dissolved oxygen concentration was …

Methods For Sampling Sequential Annual Bone Growth Layers For Stable Isotope Analysis, Calandra N. Turner Tomaszewicz, Jeffrey A. Seminoff, Larisa Avens, Carolyn M. Kurle

United States Department of Commerce: Staff Publications

1. Stable carbon (§¹³C) and nitrogen (§¹⁵N) isotope analysis (SIA) has proven useful in addressing fundamental questions in ecology such as reconstructing trophic interactions, habitat connections and climate regime shifts. The temporal scales over which SIA can be used to address ecological problems vary depending on the protein turnover times of the analysed tissue. Hard, inert tissues, such as teeth, bones and mollusc shells, grow in regular intervals (i.e. daily or annually), and sequential sampling of these growth layers provides a time series of isotopic patterns. As a result, SIA on these tissues is useful for …

Nutritional Effects On Reproductive Performance Of Captiveadult Female Coyotes (Canis Latrans), Eric M. Gese, Beth M. Roberts, Frederick F. Knowlton

United States Department of Agriculture Wildlife Services: Staff Publications

Interactions between animals and their environment are fundamental to ecological research. Field studies of coyote (Canis latrans) reproductive performance suggest mean litter size changes in response to prey abundance. However, this relationship has been assessed primarily by using carcasses collected from trappers. The objective of this study was to assess whether nutritional manipulation prior to mating affected reproduction in adult female coyotes. We examined the effects of caloric restriction during the 7 months prior to estrus on the reproductive rates of 11 captive female coyotes and the subsequent initial survival of pups through two reproductive cycles. This was …